IS: 9316 (Part 4) – 1988
DETERMINATION OF TOTAL SOLID CONTENT
1. SCOPE
1.1 This standard prescribes a method for determination of total solid content of natural rubber
latex concentrates whi8ch contains preservative agent and which has been prepared by some
type of concentration process, and also for determination of total solids content of synthetic
rubber lattices.
1.1.1 The method is not necessarily suitable for lattices from natural sources other than Hevea
brasiliensis or for compounded latex, vulcanized latex or artificial dispersion of rubber.
latex concentrates whi8ch contains preservative agent and which has been prepared by some
type of concentration process, and also for determination of total solids content of synthetic
rubber lattices.
1.1.1 The method is not necessarily suitable for lattices from natural sources other than Hevea
brasiliensis or for compounded latex, vulcanized latex or artificial dispersion of rubber.
2. METHOD FOR TAKING OUT SAMPLES
2.1 The method for taking out samples shall be in accordance with the method prescribed in IS :
9316 (part 5) – 1988.
9316 (part 5) – 1988.
3. OUTLINE OF THE METHOD
3.1 A test portion is heated to constant mass in an oven under specified condition, either at
atmospheric pressure or under vacuum, depending on the type of latex. The total solids
content is determined by weighing before and after heating.
atmospheric pressure or under vacuum, depending on the type of latex. The total solids
content is determined by weighing before and after heating.
4. APPARATUS
4.1 Glass Petri Dish
4.2 Oven – Capable of being maintained at 70 ± 2°C or 105 ± 2°C.
4.3 Vacuum Oven – Capable of being maintained at 125 ± 2°C.
4.2 Oven – Capable of being maintained at 70 ± 2°C or 105 ± 2°C.
4.3 Vacuum Oven – Capable of being maintained at 125 ± 2°C.
5. PROCEDURE
5.1 For natural rubber latex concentrate, proceed according to 5.1.1 and for synthetic rubber
latex proceed according to 5.1.1 or 5.1.2.
5.1.1 Heating at Atmospheric Pressure – Weigh, to the nearest 1mg, a dish, together with its
cover. Pour in to the dish 2± 0.5g of latex replace the cover and weigh to the nearest 1mg.
gently swirl the contents of the dish to ensure that the latex covers the bottom. If desired,
approximately 1ml of distilled water or water of equivalent purity may be added mixed well
with the latex by swirling. Place the dish uncovered in the oven so that it is horizontal and heat
it at either 70± 2°C or 105 ± 2°C until the sample has lost its whiteness, or for 16h or 2h
respectively. Allow to cool in desiccators, replace the cover and weigh. Return the dish,
uncovered, to the oven for 30min if the drying temperature 70± 2°C or for 15min if the drying
temperature is 105± 2°C. Allow to cool in desiccators, replace the cover and reweigh. Repeat
the drying procedure at intervals of 30min or 15min, as appropriate, until the loss in mass
between two successive weightings is less than 1mg.
5.1.2 Heating at reduced pressure – Weigh, to the nearest 1mg, a dish together with its cover.
Pour in to the dish 1± 0.2gm of latex, replace the cover and weigh to the nearest 0.1mg.
Remove the cover add 1ml of distilled water or water of equivalent purity and mix well by
swirling to ensure that the latex covers the bottom of the dish.
Place the dish, uncovered in the vacuum oven so that it is horizontal. Reduce the
pressure slowly, to avoid foaming and splattering, and heat at 125 ± 2°C for 45 to 60min at a
pressure below 20kPa. Allow to cool in a desiccator, replace the cover and weigh. Repeat the
drying procedure at intervals of 15min until the loss in mass between two successive weighing
is less than 0.5mg.
latex proceed according to 5.1.1 or 5.1.2.
5.1.1 Heating at Atmospheric Pressure – Weigh, to the nearest 1mg, a dish, together with its
cover. Pour in to the dish 2± 0.5g of latex replace the cover and weigh to the nearest 1mg.
gently swirl the contents of the dish to ensure that the latex covers the bottom. If desired,
approximately 1ml of distilled water or water of equivalent purity may be added mixed well
with the latex by swirling. Place the dish uncovered in the oven so that it is horizontal and heat
it at either 70± 2°C or 105 ± 2°C until the sample has lost its whiteness, or for 16h or 2h
respectively. Allow to cool in desiccators, replace the cover and weigh. Return the dish,
uncovered, to the oven for 30min if the drying temperature 70± 2°C or for 15min if the drying
temperature is 105± 2°C. Allow to cool in desiccators, replace the cover and reweigh. Repeat
the drying procedure at intervals of 30min or 15min, as appropriate, until the loss in mass
between two successive weightings is less than 1mg.
5.1.2 Heating at reduced pressure – Weigh, to the nearest 1mg, a dish together with its cover.
Pour in to the dish 1± 0.2gm of latex, replace the cover and weigh to the nearest 0.1mg.
Remove the cover add 1ml of distilled water or water of equivalent purity and mix well by
swirling to ensure that the latex covers the bottom of the dish.
Place the dish, uncovered in the vacuum oven so that it is horizontal. Reduce the
pressure slowly, to avoid foaming and splattering, and heat at 125 ± 2°C for 45 to 60min at a
pressure below 20kPa. Allow to cool in a desiccator, replace the cover and weigh. Repeat the
drying procedure at intervals of 15min until the loss in mass between two successive weighing
is less than 0.5mg.
6. CALCULATION
6.1 Calculate the total solids content (TSC), expressed as percentage by mass, using the
formula.
TSC, percentage by mass = M1 × 100
Where M0
M0 = mass, in g, of the test portion; and
M1 = mass, in g, of the dried material.
NOTE – The result of duplicate determinations shall not differ by more than 0.2%
formula.
TSC, percentage by mass = M1 × 100
Where M0
M0 = mass, in g, of the test portion; and
M1 = mass, in g, of the dried material.
NOTE – The result of duplicate determinations shall not differ by more than 0.2%
7. TEST REPORT
7.1 The test report shall include the following particulars:
a) Reference to this standard;
b) Identification of the test sample;
c) The results, and the form in which they are expressed;
d) Any unusual features noted during the determination; and
e) Any operation not included in this standard to which reference is made, or regarded as
optional.
a) Reference to this standard;
b) Identification of the test sample;
c) The results, and the form in which they are expressed;
d) Any unusual features noted during the determination; and
e) Any operation not included in this standard to which reference is made, or regarded as
optional.
thank you so much
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